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A photo of Kiehl's Alpha-Hydroxy Acid Skincare


Understanding The Skin Benefits Of Alpha-Hydroxy Acids

Alpha-hydroxy acid products can benefit your skin in many ways. Learn what AHA is, how it works, and how to incorporate it into your routine.

We get it: The idea of putting acid on your face may initially seem like an intimidating thought. Yet, using the right ones as part of a proper skincare routine can help improve your skin's appearance and keep it looking younger for longer. One of our favorites is alpha-hydroxy acid (AHA), a mild exfoliant. Unlike harsher acids used for in-office chemical peels, alpha-hydroxy acid products made for home use are gentler formulations. But what is alpha-hydroxy acid?

Ahead, learn all about what AHA is, how it works and, most importantly, how alpha-hydroxy acid benefits your skin. Read on to learn all about AHA skincare. Plus, how you can incorporate alpha-hydroxy products into your routine.

What Is AHA?

If you're hesitant to dive into the world of AHA skin products, rest assured. Alpha-hydroxy acids are one of the most extensively researched and validated skincare products. AHA is actually an umbrella term for types of organic acids. They're found throughout nature in sugarcane, milk, and fruits—though the kinds used in some skincare products are synthetic.

The most common alpha-hydroxy acids in skincare are lactic acid and glycolic acid, which have been used to treat a variety of skin concerns for decades. AHA skincare products gently exfoliate dead skin cells to reveal fresher, healthier-looking skin underneath. By doing so, they stimulate the growth of new cells, which provides a variety of benefits with minimal risk of irritation.

What Are The Biggest Alpha-Hydroxy Acid Benefits?

Despite being a mild exfoliant, alpha-hydroxy acid benefits your skin in numerous ways. But for our purposes here, we'll focus on the major ones. It can visibly brighten skin, smooth the appearance of fine lines and wrinkles, and help address dark spots and other discolorations. AHA can also unblock and cleanse pores, which can reduce the appearance of enlarged ones. Overall, by promoting skin rejuvenation, continued use of alpha-hydroxy acid can help bolster the condition of your skin for a younger, healthier look.

If you're seeking to reap alpha-hydroxy acid's benefits on a tight timeline, we recommendClearly Corrective Accelerated Clarity Renewing Ampoules. This intensive 14-day treatment can amplify your current routine, or you can use it to help your skin fight stressors like changes in the seasons, sun damage, or pollution. You can even reach for them a couple of weeks before a big event to help make sure your skin is looking and feeling its best. The highly concentrated formula, which contains glycolic, lactic, and phytic acids combined with Activated C, helps achieve maximum radiance—over 33% visibly brighter skin, to be exact.*

*Based on expert grading in a 2-week clinical study of 85 panelists in Brazil.

To give your visage even more oomph, pair it with Clearly Corrective Dark Spot Corrector. This targeted treatment with antioxidantpeony extract, buffered salicylic acid (a beta-hydroxy acid!), and Activated C is clinically proven to reduce hyperpigmentation by 49%, dark spots by 39%, and post-acne marks by 27%. It's also dermatologist-tested and safe on all skin types.*

*Based on a 12-week clinical study of 17 women with all skin types presented with a mild to moderate severity of attributes, including post-inflammatory hyperpigmentation.

Who Should Use AHAs?

So, alpha-hydroxy acid products help revitalize your skin's appearance—and an AHA exfoliant like our Clearly Corrective ampoules can help do that in as little as two weeks. But is there anyone who shouldn't use it?

Fortunately, AHA skin formulas can be used to safely slough all types of skin—including oily, acne-prone skin. That said, if you have sensitive skin, you may want to start using AHAs slowly, such as every other day, to reduce your chances of irritation. This gives your skin the opportunity to acclimate to them, then you can gradually work your way up to daily use.

How To Use Alpha-Hydroxy Acids

Now here comes the fun part—pampering yourself with an AHA-centric skincare routine. Start by cleansing (as you always should). We recommend antioxidant-rich Clearly Corrective Brightening & Exfoliating Daily Cleanser, a purifying cleanser that gently exfoliates while removing dirt, oil, and pollution from your skin. The formula stars peony extract and white birch extract, as well as pearlstone to help refine and brighten skin. Cleanse morning and night with this dermatologist-tested cleanser for a smoother, more radiant appearance.

Next, apply an essence, like our new Ferulic Brew Rejuvenating Facial Essence. Inspired by old-world apothecary preparations, it's enriched with brassica extract that's been phyto-brewed for 120 hours. This "essential brew" is packed with antioxidants, and formulated with naturally-derived ferulic acid, as well as lactic acid and squalane. It absorbs quickly and is clinically-demonstrated to visibly improve radiance by over 22%, refine texture by more than 20%, and reduce fines lines by 18%. Use it morning and night by applying a few drops to your face, focusing on your cheeks, forehead, and chin.

*We consider ingredients to be naturally-derived if they retain more than 50% of their molecular structure after being processed from a natural source.

Follow your essence with Nightly Refining Micro-Peel Concentrate, which uses phytic acid and quinoa husk extract to work while you sleep. Gentle enough to use every night, on all skin types, this dermatologist-tested formula is clinically-demonstrated to help accelerate cell turnover to visibly even skin tone and texture.* Apply a few drops to your fingertips and press them over your face until they're absorbed. Use it after cleansing and toning, but before any other serum or your moisturizer, for radiant, glowing skin.

_*Based on an instrumental test within surface layers._Results based upon expert grading in a dermatologist-controlled clinical study.

Finish up by applying an AHA moisturizer to seal in all the hero ingredients and hydration. We like Clearly Corrective Brightening & Smoothing Moisture Treatment, which stars glycolic acid, white birch extract, and Activated C. Massage a small amount onto your skin morning and night, avoiding the eye area, for 24-hour hydration. This dermatologist-tested formula is safe for all skin types and clinically proven to help correct the appearance of discolorations and rough texture for fresher, younger-, healthier-looking skin.* You can also use it as an intensive overnight mask up to three times a week to reap all of its benefits.

*Results based upon a clinical study of upper layers of the skin.

Kiehl's CC Brightening Cleanser

Can I Use AHAs Every Day?

You may be wondering if there's a thing as using AHAs too often. But there's no need to worry. Once your skin acclimates to them, it should be perfectly fine to use them every day. We'd be remiss, however, if we didn't stress the importance of wearing sunscreen—especially when using products with AHAs in them.

Aside from the fact that you should be wearing sunscreen every day regardless, alpha-hydroxy acids are known to cause increased sensitivity to UV rays. One study found that after four weeks of use, people who used AHAs were 18% more sensitive to the sun. Sensitivity to UV-induced skin cell damage also doubled on average.I So slather up!

We can't get enough of Super Fluid Daily UV Defense SPF 50+. This lightweight, non-comedogenic facial sunscreen won't clog your pores. What it will do is provide advanced protection from environmental aggressors including UVA and UVB rays, as well as pollution. The formula with antioxidants baicalin and vitamin E absorbs quickly with a matte finish, and will help shield your skin from early signs of aging. Apply it daily in the morning alone or under foundation to protect your skin and all your AHA skincare progress.

Next: Your skin isn't the only part of your body that can benefit from acids. Learn more about How Amino Acids Benefit Your Hair and Skin.

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